The main thing I would do is suggest you stay away from Dr Google. She is a very strange doctor who suggests the rarest, most complex and horrific ailments with the same or greater enthusiasm as anything more common and easy to cure. I completely understand that as a parent you put yourself through hell because of your child but anything you can do to not put yourself through it, I encourage you to do. You’ll do more good enjoying the age that your son is than to spend too long worrying about what might never be.
I’ve done a bit of a search through the posts that we have on this forum and many of them are very old, so it is less likely that writing back on these would get you a response but the following thread sets out what I believe to be the case. Have a read of it.
What you will see is that intracranial AVMs recur the least frequently and I agree that surgery tends to be the least likely to recur. So your son has the very best chance of being fully well after his surgery.
If I remember rightly, your son had his operation 2 or three months ago. This is still very early after a major trauma to his head. He needs time to get better. We should also think that undergoing lots of scans using radiation isn’t good for us, either, so it is best to wait for his operation to fully heal and not want to have a scan every month or so. I know exactly how you feel: I think I wanted lots of scans at one point but really, they’re not good for you, so should be kept for when they are necessary.
You can search for things like “recur” using the magnifying glass, above, to find all of the stories that might be relevant. I would caution that we moved web sites or “web platform” in summer of 2016, so older posts you are less likely to find people still active in the site.
Very best wishes,
Richard